Add basic test coverage for files that don't require any config options:
* part of math.h (what seem to be the most commonly used macros)
* gcd.c
* lcm.c
* int_sqrt.c
* reciprocal_div.c
(Ignored int_pow.c since it's a simple textbook algorithm.)
These tests aren't particularly interesting, but they
* provide short and simple examples of parameterized tests
* provide a place to add tests for any new files in this dir
* are written so adding new test cases to cover edge cases should be easy
* looking at code coverage, we hit all the branches in the .c files
Signed-off-by: Daniel Latypov
Reviewed-by: David Gow
---
Changes since v5:
* add in test cases for roundup/rounddown
* address misc comments from David
Changes since v4:
* add in test cases for some math.h macros (abs, round_up/round_down,
div_round_down/closest)
* use parameterized testing less to keep things terser
Changes since v3:
* fix `checkpatch.pl --strict` warnings
* add test cases for gcd(0,0) and lcm(0,0)
* minor: don't test both gcd(a,b) and gcd(b,a) when a == b
Changes since v2: mv math_test.c => math_kunit.c
Changes since v1:
* Rebase and rewrite to use the new parameterized testing support.
* misc: fix overflow in literal and inline int_sqrt format string.
* related: commit 1f0e943df68a ("Documentation: kunit: provide guidance
for testing many inputs") was merged explaining the patterns shown here.
* there's an in-flight patch to update it for parameterized testing.
---
lib/math/Kconfig | 12 ++
lib/math/Makefile | 2 +
lib/math/math_kunit.c | 291 ++
3 files changed, 305 insertions(+)
create mode 100644 lib/math/math_kunit.c
diff --git a/lib/math/Kconfig b/lib/math/Kconfig
index f19bc9734fa7..a974d4db0f9c 100644
--- a/lib/math/Kconfig
+++ b/lib/math/Kconfig
@@ -15,3 +15,15 @@ config PRIME_NUMBERS
config RATIONAL
bool
+
+config MATH_KUNIT_TEST
+ tristate "KUnit test for lib/math and math.h" if !KUNIT_ALL_TESTS
+ depends on KUNIT
+ default KUNIT_ALL_TESTS
+ help
+ This builds unit tests for lib/math and math.h.
+
+ For more information on KUnit and unit tests in general, please
refer
+ to the KUnit documentation in Documentation/dev-tools/kunit/.
+
+ If unsure, say N.
diff --git a/lib/math/Makefile b/lib/math/Makefile
index be6909e943bd..30abb7a8d564 100644
--- a/lib/math/Makefile
+++ b/lib/math/Makefile
@@ -4,3 +4,5 @@ obj-y += div64.o gcd.o lcm.o int_pow.o int_sqrt.o
reciprocal_div.o
obj-$(CONFIG_CORDIC) += cordic.o
obj-$(CONFIG_PRIME_NUMBERS)+= prime_numbers.o
obj-$(CONFIG_RATIONAL) += rational.o
+
+obj-$(CONFIG_MATH_KUNIT_TEST) += math_kunit.o
diff --git a/lib/math/math_kunit.c b/lib/math/math_kunit.c
new file mode 100644
index ..556c23b17c3c
--- /dev/null
+++ b/lib/math/math_kunit.c
@@ -0,0 +1,291 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Simple KUnit suite for math helper funcs that are always enabled.
+ *
+ * Copyright (C) 2020, Google LLC.
+ * Author: Daniel Latypov
+ */
+
+#include
+#include
+#include
+#include
+#include
+
+static void abs_test(struct kunit *test)
+{
+ KUNIT_EXPECT_EQ(test, abs((char)0), (char)0);
+ KUNIT_EXPECT_EQ(test, abs((char)42), (char)42);
+ KUNIT_EXPECT_EQ(test, abs((char)-42), (char)42);
+
+ /* The expression in the macro is actually promoted to an int. */
+ KUNIT_EXPECT_EQ(test, abs((short)0), 0);
+ KUNIT_EXPECT_EQ(test, abs((short)42), 42);
+ KUNIT_EXPECT_EQ(test, abs((short)-42), 42);
+
+ KUNIT_EXPECT_EQ(test, abs(0), 0);
+ KUNIT_EXPECT_EQ(test, abs(42), 42);
+ KUNIT_EXPECT_EQ(test, abs(-42), 42);
+
+ KUNIT_EXPECT_EQ(test, abs(0L), 0L);
+ KUNIT_EXPECT_EQ(test, abs(42L), 42L);
+ KUNIT_EXPECT_EQ(test, abs(-42L), 42L);
+
+ KUNIT_EXPECT_EQ(test, abs(0LL), 0LL);
+ KUNIT_EXPECT_EQ(test, abs(42LL), 42LL);
+ KUNIT_EXPECT_EQ(test, abs(-42LL), 42LL);
+
+ /* Unsigned types get casted to signed. */
+ KUNIT_EXPECT_EQ(test, abs(0ULL), 0LL);
+ KUNIT_EXPECT_EQ(test, abs(42ULL), 42LL);
+}
+
+static void int_sqrt_test(struct kunit *test)
+{
+ KUNIT_EXPECT_EQ(test, int_sqrt(0UL), 0UL);
+ KUNIT_EXPECT_EQ(test, int_sqrt(1UL), 1UL);
+ KUNIT_EXPECT_EQ(test, int_sqrt(4UL), 2UL);
+ KUNIT_EXPECT_EQ(test, int_sqrt(5UL), 2UL);
+ KUNIT_EXPECT_EQ(test, int_sqrt(8UL), 2UL);
+ KUNIT_EXPECT_EQ(test, int_sqrt(1UL << 30), 1UL << 15);
+}
+
+static void round_up_test(struct kunit *test)
+{
+ KUNIT_EXPECT_EQ(test, round_up(0, 1), 0);
+ KUNIT_EXPECT_EQ(test, round_up(1, 2), 2);
+ KUNIT_EXPECT_EQ(test, round_up(3, 2), 4);
+ KUNIT_EXPECT_EQ(test, round_up((1 << 30) - 1, 2), 1 << 30);
+ KUNIT_EXPECT_EQ(test, round_up((1 << 30) - 1, 1 << 29), 1 << 30);
+}
+
+static void round_down_test(struct kunit *test)
+{
+ KUNIT_EXPECT_EQ(test, round_down(0, 1),
